
\paragraph{MySQL database.}
Containers are usually disposable, so once it
is destroyed, all the data inside the containers are lost.
For this lab, we do want to keep the data in the
MySQL database, so we do not lose our work when we shutdown
our container. To achieve this,
we have mounted the \texttt{mysql\_data} folder on
the host machine (inside
\texttt{Labsetup}, it will be created after the
MySQL container runs once) to the
\texttt{/var/lib/mysql} folder
inside the MySQL container.
This folder is where
MySQL stores its database. Therefore,
even if the container is destroyed,
data in the database are still kept.
If you do want to start from a clean
database, you can remove this folder:

\begin{lstlisting}
$ sudo rm -rf mysql_data
\end{lstlisting}

